diff --git a/views/bootstrap/class.Bootstrap.php b/views/bootstrap/class.Bootstrap.php
index ae5228d2c..e4087d929 100644
--- a/views/bootstrap/class.Bootstrap.php
+++ b/views/bootstrap/class.Bootstrap.php
@@ -2100,6 +2100,15 @@ $(document).ready(function() {
 		echo self::getAttributeEditField($attrdef, $attribute, $fieldname, $norequire, $namepostfix, $alwaysmultiple);
 	} /* }}} */
 
+	/**
+	 * Return html code for an input/select field of an attribute
+	 *
+	 * The passed attribute ($attribute) can either be an object of type
+	 * SeedDMS_Core_Attribute, scalar or an array. A scalar or array is
+	 * passed when the method is called to create the search form. In that
+	 * case $attribute has the value from the post data after submitting the
+	 * search form.
+	 */
 	function getAttributeEditField($attrdef, $attribute, $fieldname='attributes', $norequire=false, $namepostfix='', $alwaysmultiple=false) { /* {{{ */
 		$dms = $this->params['dms'];
 		$attr_id = $fieldname.'_'.$attrdef->getId().($namepostfix ? '_'.$namepostfix : '');
@@ -2136,10 +2145,19 @@ $(document).ready(function() {
 			$content .= $this->getDocumentChooserHtml("attr".$attrdef->getId(), M_READ, -1, $target, $attr_name);
 			break;
 		case SeedDMS_Core_AttributeDefinition::type_user:
-			$target = $attribute ? $attribute->getValueAsArray() : [];
 			$objvalue = [];
-			foreach($target as $t)
-				$objvalue[] = $t->getId();
+			if($attribute) {
+				if(is_object($attribute)) {
+					$target = $attribute->getValueAsArray();
+					foreach($target as $t)
+						$objvalue[] = $t->getId();
+				} elseif(is_array($attribute)) {
+					foreach($attribute as $t)
+						$objvalue[] = $t;
+				} else {
+					$objvalue[] = $attribute;
+				}
+			}
 			$users = $dms->getAllUsers();
 			if($users) {
 				$allowempty = $attrdef->getMinValues() == 0;
@@ -2159,10 +2177,19 @@ $(document).ready(function() {
 			}
 			break;
 		case SeedDMS_Core_AttributeDefinition::type_group:
-			$target = $attribute ? $attribute->getValueAsArray() : [];
 			$objvalue = [];
-			foreach($target as $t)
-				$objvalue[] = $t->getId();
+			if($attribute) {
+				if(is_object($attribute)) {
+					$target = $attribute->getValueAsArray();
+					foreach($target as $t)
+						$objvalue[] = $t->getId();
+				} elseif(is_array($attribute)) {
+					foreach($attribute as $t)
+						$objvalue[] = $t;
+				} else {
+					$objvalue[] = $attribute;
+				}
+			}
 			$groups = $dms->getAllGroups();
 			if($groups) {
 				$allowempty = $attrdef->getMinValues() == 0;
diff --git a/views/bootstrap/class.DocumentVersionDetail.php b/views/bootstrap/class.DocumentVersionDetail.php
index d11d0ad94..4a15a6e57 100644
--- a/views/bootstrap/class.DocumentVersionDetail.php
+++ b/views/bootstrap/class.DocumentVersionDetail.php
@@ -353,7 +353,7 @@ class SeedDMS_View_DocumentVersionDetail extends SeedDMS_Theme_Style {
 					print "<li>".$arr[0].": ".$arr[1]."</li>\n";
 				} else {
 					$attrdef = $attribute->getAttributeDefinition();
-					print "<li>".htmlspecialchars($attrdef->getName()).": ".htmlspecialchars(implode(', ', $attribute->getValueAsArray()))."</li>\n";
+					print "<li>".htmlspecialchars($attrdef->getName()).": ".htmlspecialchars($attribute->getValueAsString())."</li>\n";
 				}
 			}
 		}
diff --git a/views/bootstrap/class.Search.php b/views/bootstrap/class.Search.php
index caeaa4fba..4d2e62b8c 100644
--- a/views/bootstrap/class.Search.php
+++ b/views/bootstrap/class.Search.php
@@ -813,9 +813,9 @@ $(document).ready(function() {
 					} elseif(in_array($attrdef->getType(), [SeedDMS_Core_AttributeDefinition::type_int, SeedDMS_Core_AttributeDefinition::type_float]) && !$attrdef->getValueSet()) {
 						$this->formField(htmlspecialchars($attrdef->getName().' ('.getMLText('from').')'), $this->getAttributeEditField($attrdef, !empty($attributes[$attrdef->getID()]['from']) ? $attributes[$attrdef->getID()]['from'] : '', 'attributes', true, 'from'));
 						$this->formField(htmlspecialchars($attrdef->getName().' ('.getMLText('to').')'), $this->getAttributeEditField($attrdef, !empty($attributes[$attrdef->getID()]['to']) ? $attributes[$attrdef->getID()]['to'] : '', 'attributes', true, 'to'));
-
-					} else
-						$this->formField(htmlspecialchars($attrdef->getName()), $this->getAttributeEditField($attrdef, isset($attributes[$attrdef->getID()]) ? $attributes[$attrdef->getID()] : '', 'attributes', true, '', true));
+					} else {
+						$this->formField(htmlspecialchars($attrdef->getName()), $this->getAttributeEditField($attrdef, isset($attributes[$attrdef->getID()]) ? $attributes[$attrdef->getID()] : '', 'attributes', true, '', false));
+					}
 				}
 			}
 		}
diff --git a/views/bootstrap4/class.Bootstrap4.php b/views/bootstrap4/class.Bootstrap4.php
index 1bdd4e5cd..c2be23b6d 100644
--- a/views/bootstrap4/class.Bootstrap4.php
+++ b/views/bootstrap4/class.Bootstrap4.php
@@ -2044,6 +2044,15 @@ $(document).ready(function() {
 		echo self::getAttributeEditField($attrdef, $attribute, $fieldname, $norequire, $namepostfix, $alwaysmultiple);
 	} /* }}} */
 
+	/**
+	 * Return html code for an input/select field of an attribute
+	 *
+	 * The passed attribute ($attribute) can either be an object of type
+	 * SeedDMS_Core_Attribute, scalar or an array. A scalar or array is
+	 * passed when the method is called to create the search form. In that
+	 * case $attribute has the value from the post data after submitting the
+	 * search form.
+	 */
 	function getAttributeEditField($attrdef, $attribute, $fieldname='attributes', $norequire=false, $namepostfix='', $alwaysmultiple=false) { /* {{{ */
 		$dms = $this->params['dms'];
 		$attr_id = $fieldname.'_'.$attrdef->getId().($namepostfix ? '_'.$namepostfix : '');
@@ -2077,18 +2086,27 @@ $(document).ready(function() {
 			$content .= "<input type=\"text\" class=\"form-control\" id=\"".$attr_id."\" name=\"".$attr_name."\" value=\"".htmlspecialchars($objvalue)."\"".((!$norequire && $attrdef->getMinValues() > 0) ? ' required="required"' : '')." data-rule-number=\"true\"/>";
 			break; */
 		case SeedDMS_Core_AttributeDefinition::type_folder:
-			$target = $attribute ? $attribute->getValue() : null;
+			$target = $attribute ? (is_object($attribute) ? $attribute->getValue() : $attribute) : null;
 			$content .= $this->getFolderChooserHtml("attr".$attrdef->getId(), M_READWRITE, -1, $target, $attr_name, false);
 			break;
 		case SeedDMS_Core_AttributeDefinition::type_document:
-			$target = $attribute ? $attribute->getValue() : null;
+			$target = $attribute ? (is_object($attribute) ? $attribute->getValue() : $attribute) : null;
 			$content .= $this->getDocumentChooserHtml("attr".$attrdef->getId(), M_READ, -1, $target, $attr_name);
 			break;
 		case SeedDMS_Core_AttributeDefinition::type_user:
-			$target = $attribute ? $attribute->getValueAsArray() : [];
 			$objvalue = [];
-			foreach($target as $t)
-				$objvalue[] = $t->getId();
+			if($attribute) {
+				if(is_object($attribute)) {
+					$target = $attribute->getValueAsArray();
+					foreach($target as $t)
+						$objvalue[] = $t->getId();
+				} elseif(is_array($attribute)) {
+					foreach($attribute as $t)
+						$objvalue[] = $t;
+				} else {
+					$objvalue[] = $attribute;
+				}
+			}
 			$users = $dms->getAllUsers();
 			if($users) {
 				$allowempty = $attrdef->getMinValues() == 0;
@@ -2108,10 +2126,19 @@ $(document).ready(function() {
 			}
 			break;
 		case SeedDMS_Core_AttributeDefinition::type_group:
-			$target = $attribute ? $attribute->getValueAsArray() : [];
 			$objvalue = [];
-			foreach($target as $t)
-				$objvalue[] = $t->getId();
+			if($attribute) {
+				if(is_object($attribute)) {
+					$target = $attribute->getValueAsArray();
+					foreach($target as $t)
+						$objvalue[] = $t->getId();
+				} elseif(is_array($attribute)) {
+					foreach($attribute as $t)
+						$objvalue[] = $t;
+				} else {
+					$objvalue[] = $attribute;
+				}
+			}
 			$groups = $dms->getAllGroups();
 			if($groups) {
 				$allowempty = $attrdef->getMinValues() == 0;